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    <meta charset="UTF-8">
    <title>Title</title>
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<script>
    document.write("<h3>打印倒正金字塔直线</h3>");
    for (var i = 61; i > 0; i -= 10) {//打印倒金字塔
        document.write("<hr width=" + i + "%/>");
    }
    for (var j = 11; j < 70; j = j + 10) {//打印正金字塔
        document.write("<hr width=" + j + "%/>");
    }
</script>


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